What’s awakeFromNib for?

Downcasting optionals in Swift: as? Type, or as! Type?

Any vs. AnyObject in Swift 3.0 – Luna An – Medium

Enums in swift – Abhimuralidharan – Medium

Swift Closures

Understanding Event Handling, Responders, and the Responder Chain | Apple Developer Documentation

ios responder chain


참고 ios docs ) https://developer.apple.com/documentation/uikit/touches_presses_and_gestures/understanding_event_handling_responders_and_the_responder_chain